Increased alkalinity is a known factor in the development of kidney stones. The study found that the amount of citrate and malate contained in popular diet sodas may inhibit the development of calcium stones. Researchers measured the citrate and malate content of 15 popular diet sodas and found that Diet Sunkist Orange contained the greatest amount of total alkali and Diet 7-Up had the greatest amount of citrate as alkali. In a news release from the American Urologial Association, Dr. Anthony Y. Smith said,"This study by no means suggests that patients with recurrent kidney stones should trade in their water bottles for soda cans. However, this study suggests instead that patients with stone disease who do not drink soda may benefit from moderate consumption."